(L-R) Britain's Catherine, Duchess of Cambridge holding her daughter Princess Charlotte, Prince George and Britain's Prince William, Duke of Cambridge stand on the balcony of Buckingham Palace to watch a fly-past of aircrafts by the Royal Air Force, in London on June 11, 2016. .Trooping The Colour and the fly-past are part of a weekend of events to celebrate the Queen's 90th birthday. / AFP / JUSTIN TALLIS